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Eight diterpenes and norditerpenes including five new xenicane metabolites (4−8) have been isolated from the gorgonian Acalycigorgia inermis. The structures of these compounds have been determined by combined spectroscopic analysis. The new compounds exhibited significant cytotoxicity against a human leukemia cell-line.

InGaP/InGaAIP visible-light laser diodes with a metal-clad ridge waveguide structure have been fabricated. Compressively strained SCH-MQW structures were grown by low-pressure MOCVD and the lasing wavelength was 690 nm. The threshold current was 28 mA at 25°C for a 400 µm cavity and 5 µm stripe width. CW operation was obtained as the cleaved device by employing thick gold layer as a heat spreader. The light-output power versus CW current was linear up to a maximum light output power of 38 mW. Stable operation of the fundamental transverse optical mode was maintained up to 30 mW. These results show that this metal-clad ridge waveguide structure provides sufficient current confinement even under high light output power operation.

The lutropin/choriogonadotropin receptor is a seven-helix transmembrane (TM) receptor. A unique feature of TM helices is the content of Pro, which generally is absent in alpha helices of globular proteins. Because Pro disrupts helices and introduces a approximately 26 degrees kink, it has been speculated that Pro plays a crucial role in the structure of TM helices, exoloops, and cytoloops of TM receptors. To examine the roles of the five TM Pros of the lutropin/choriogonadotropin receptor, these residues were individually substituted. Mutant receptors were examined for surface expression, hormone binding, and cAMP induction. Surface expression was monitored after introducing the flag epitope into the receptors. Flag epitopes slightly affected cAMP induction but not hormone binding or surface expression of receptors as monitored by immunofluorescence microscopy and 125I-anti-flag antibody. The results indicate that Pro479 in TM 4 and Pro598 in TM 7 play important yet contrasting roles. Pro479 is crucial for hormone binding at the cell surface but not after solubilization of the receptor. This is more likely due to the Pro side chain than the Pro-induced kink. Pro598 is important for surface expression. The kinks of Pro463 of TM 4, Pro562 of TM 6, or Pro591 of TM 7 are not important because the substitution of Phe for these residues did not significantly impact surface expression, hormone binding, and cAMP induction.

The GalnP/AlGalnP layers are known as attractive materials for 600 nm band laser diodes. In this paper, a Bragg reflector between GaAs substrate and n-cladding layer was applied for the reduction in the lasing threshold. In a SCH-MQW structure, a Bragg reflector was composed of alternating λ/4n layers of AlAs and AlGaAs layers, 12.5 pairs. The effect of Bragg reflector on the threshold current and spontaneous emission intensity was appreciable because most of spontaneously emitted photons were reflected from a Bragg reflector and carriers were regenerated in the GalnP active layer.

Frequency reports in 1967-1969 for 83 foods were compared to frequency reports for the same foods asked retrospectively in 1982-1983 about use in 1967-1969 for 1,184 respondents aged 45-64 in the Tecumseh Community Health Study cohort. Food frequency reports of the current (1982-1983) diet were also compared to baseline reports to indicate diet stability and to retrospective reports to indicate the influence of current diet on retrospective reporting. Comparisons were also made for 13 food groups and vitamin A and C indices. Short-term reproducibility of seven foods, measured by two reports 1-3 weeks apart in 1967-1969, was compared to long-term reproducibility for the same foods. Short-term reproducibility was consistently greater than long-term. Reproducibility was associated positively with stability of use. For the two nutrient indices and nine of the ten food groups examined, mean intake estimated from the retrospective report differed significantly from mean intake from the baseline report. Agreement between retrospective and current reports exceeded agreement between retrospective and baseline reports, indicating that retrospective reports were greatly influenced by current behavior; yet, the retrospective reports were better indicators of baseline consumption than were the current reports. While misclassification from use of the retrospective report to measure baseline consumption was large, risk differences may still be detected with usual sample sizes.

Analysis of mortality among men who were employed by Reserve Mining Company from 1952 to 1976 has been carried out. Follow-up was conducted with standard methods, including searches by the Social Security Administration. Occupational exposures to dust were based on personal samples taken over the past five years by the industrial hygiene department of the company. Smoking habits were obtained by mailed questionnaires or telephone interviews. A modified life table method was used to compare death rates of the employees with those expected for white males in the state of Minnesota. Comparisons were also made with US rates for white males. The results showed that the death rates for all causes were significantly below expectation. Deaths from malignant diseases were marginally below those expected for the state. Exposures to total dust, to silica dust, or to fiber were low. There was no relationship between mortality and estimated lifetime dust exposures, nor was there any suggestion that deaths from malignant neoplasms were increased after 15 to 20 years latency. In contrast, there was a strong relationship between smoking habits and mortality from all causes, from cardiovascular diseases, and from cancer. This study does not suggest any increase in cancer mortality from taconite exposure.